Combination pothead and series cut-out



Nov. 4, 1930. p. F, WlLLlAMS 1,780,413

COMBINATION POTHEAD AND SERIES CUT-OUT Filed May 16, 1925 Patented lNov. 4, 193() UNITED STATES PATENT OFFICE PAUL F. WILLIAMS, OF CHICAGO,ILLINOIS, ASSIGNOR T0 G. & W. ELECTRIC' SPECIALTY CO., OF CHICAGO,ILLINOIS, A CORPORATION OF ILLINOIS Application' mea may 1s, 1935.serial No. 30,764.

This invention relates to a combination pothead and series cut-out andis an improvement upon the arrangement disclosed in my alier Patent N o.1,190,836, granted July 1l,

.One object of the invention is to provide a combination pothead andseries cut-out in which the yieldable contacts are so shaped andarranged as to prevent fatigue of the metal of said contacts .and topositively insure engagement ot' said contacts when the normalseparating medium of said contacts is withdrawn.

Another object is to provide a combination pothead and series cut-outhaving cooperating, confined, yieldable contacts which are adapted to beseparated for making a lighting circuit eiective, which contacts tend tomove into engagement with each other to form a circuit around saidlighting circuit, said contacts cooperating and being so arranged andshaped as to prevent fatigue of same and to insure their interengagementwhen the separating influence is withdrawn.

Another object is to provide simple and improved means torspacing thecontacts carried by the removable top of the pothead and which areconnected to the lighting circuit.

-Another object is to provide simple, durable and ecient bracket meansfor not only clamping the pothead in position, but also, forsimultaneously clamping in position the cable or cablfentering saidpothead.

Another object is to provide a simple. reliable, durable and ecientcombination of pothead and series cut-out adapted to meet all therequirements under service conditions.

These and other objects are accomplished by means of the arrangementdisclosed on the accompanying` sheet of drawings, in which Fig. 1 is avertical sectional view, parts being shown in elevation, of my improvedcombination pothead and series cut-out;

Fig. 2 is a sectional view taken in the plane of line 2-2 of Fig. l;

Fig. 3 is a front elevation, a part being in section, of the pothead topremoved from the body of the pothead and showingan insulating buttonthreaded into the contacts for not only separating said contacts butpreventing displacement of said insulating button;

Fig. 4 is a detailed vertical sectional view showing the main springcontact members in engagement with each other for completing a circuitaround the lighting circuit when the top of the dpothead with itscontacts are removed; an

Fig. 5 is a detailed sectional view taken in plane 5 5 of Fig. 1.

The various novel features of this invention will be apparent from thefollowing description and drawings and will be particularly pointed outin the appended claims.v

My present invention is illustrated in connection with a combinationpothead and series cut-out in which the pothead 10 preferably is made ofporcelain and has two main cable receiving passageways 11 and acentrally arranged partition 12 having a. pocket 13. A cable 14 isreceived in each ofthe said passageways 11 and is electrically securedto an associated cable terminal 15 into which a screw 16 extends forsupporting the cable terminal in position with respect to a bracket 17formed in the upper portion of the body l0. A main spring Contact 18 andan auxiliary or arcing contact 19 are secured in position by each ot thescrews 16, and a cooperating screw and nut arrangement 20 locks each ofsaid contacts 18 and 19 in position.

rllhe cooperating main spring contacts 18 are confined within the pocket13 and each of said main spring contacts 18 is looped or bent uponitself, that is to say, the free end of each spring Contact is bent toform a contact engaging portion 21 and a wall engagin portion 22. Theseconined or compresse main spring contacts 18 tend to move into.

engagement with each other as shown in Fig. 4: of the drawings. lln suchposition current is supplied through one of the cables 14, then throughsaid engaging contacts 18 and out through the other cable 14. Such isthe circuit connection when the top of the pothead is removed and thelighting or other circuit is disconnected from the main supply circuit.By bending each of the main spring contacts upon itself, interengagementof said contacts'is positively-insured when the niedium which` separatessaid contacts is removed. Furthermore, by so shaping said contacts themetal thereof is prevented from becoming fatigued as quickly as is thecase with spring contacts heretofore used in combination potheads andseries cut-outs.

\ As indicated above, the pothead has a reerate with correspondingopenings 31 formed in said contacts. Said insulating button 29 not onlyacts as a spacer to prevent said contacts from moving into engagementwith each other, but, by virtue of the threaded arrangement, theinsulating button 29 is held in position against accidentaldisplacement.

As shown in Fig. 1 of the drawings, the pothead top is in its normalposition and the contacts 24 are in engagement with the associatedspring contacts 18 for separating the latter and establishing an activecircuit from one of `the cables 14 through one of the spring contacts18, one of the contacts 24, aerial cable 27, through the lightingcircult, back through aerial cable 28, the other contactA 24 and otherspring contact 18 through the other ground cable 14. With the contacts24 in am engagement with the main yieldable contacts 18, it will be seenthat the latter are under considerable compression for making a goodelectrical connection between said contact members. Also, an electricalconnection is established between the contactsv24 at the arcing contacts19.

If for any reason it is desired to remove the top of the pothead anddisconnect the contacts 24 from the yieldable contacts 18, as, forexample, when trouble has occurred 1n the llghting circuit, the top 23of said pothead is rawn awa?7 from the main body portion with the resu tthat as soon as the contacts 24 are withdrawn from the associated springcontacts 18, the latter spring into electrlcal enga ement with eachother for establlshmg a circuit directly from one ground cable 14 totheother for formin a circuit around the lightingcircuit, whic lightingcircult includes the aerial cables 27 and 28, and, upon furtherwithdrawal movement of the contacts 24, said contacts pass out ofengagement with the arcing contacts 19. It is to be noted, however, that.an electrical cir-u cuit is established between the main springcontacts 18 before the circuit is broken at the arcing contacts 19,thereby preventing any arcing, especially at the main contacts pon aninspection of Fig. 4, it will be 'appreciated that because of the bentconstruction of the springs 18, said spring contacts quickly andvigorously spring into engagement with each other for establishing anintimate electrical contact as soon. as the separating medium orcontacts 24 are withdrawn from between said spring contacts 18.-

Heretofore,the main force for pressing the spring contacts intoengagement with each other has been concentrated in the points of thespring contacts as indicated by reference characters 32. With such anarrangement, it will be understood that the metal in time will becomefatigued at such points with the result that poor contact will be formedbetween the spring contacts and ultimately may be no contact at all canbe established between same. However, with my lirnproved arrangement anintimate electrical engagement established between the spring vcontacts18 and likelihood of fatiguing of the metal of said contacts is greatlyreduced. When fitting the pothead top inplace on the main body portionof the pothead for again completing the lighting circuit, the contacts24 rst contact with the auxiliary or arcing contacts 19 before, passinginto engagement A felt gasket 35 preferably is interposed between thebracket and the pothead 10 and the parts 33 and 34 of the split bracketare pressed and held in position by two bolts 36 which pass throughopenings 37 formed in the partition 12V of the pothead and also, throughaligned openings in' the clamp parts-33 and 34. Not only do the clampmembers 33 and 34 clamp the pothead 10 for holding it in position, butthe clamp members have semi-circularfportions 38 which embrace and clampthe ground cables 14 for assisting in supporting said cables and toprevent strain on the connection between said ground cables -and thecable terminals 15. Auxiliary clamping bolts 39 are used to increase theclamping action on the cables. It will be understood that the cables 14are housdin metal sheaths 40, such as lead, said sheaths extending upinto the pothead a predetermined distance. One of the clamp parts 33 isprovided with slotted attaching legs 41 whereby the whole pothead may besecured to any suitable support.

By means of this simple, reliable and eiiicient combination pothead and/series cut-out arrangement, all of the requirements .under serviceconditions are met.

I claim:

'1. In a device of the class described, the combination of a pothead,conned yieldable contacts mounted therein, a removable top for saidpothead, spaced contacts carried thereby which when electricallyconnected with said yieldable contacts separate the latter to complete agiven circuit, said yieldable contacts springing into engagement witheach other when said other contacts are Withdrawn to form a circuitaround said other circuit, said yieldable contacts being in the form ofa loop to provide a pothead engaging portion to prevent fatigue of saineand to insure their interengagement when said other contacts areWithdrawn.

2. In a device of the class described, the combination of a pothead,cooperating coniined yieldable contacts mounted therein, associatedspaced contacts Which when electrically connected with said yieldablecontacts separate the latter to complete a given circuit, said yieldablecontacts springing into engagement with each other when said othercontacts are withdrawn to form a circuit around said rst circuit, saidyieldable contacts being bent upon themselves with their free endsengaging said pothead to prevent fatigue of same and to insure theirinterengagement when said other contacts are withdrawn.

3. In a device of the class described, the combination of a pothead,cooperating conlined yieldable contacts which are adapted to beseparated for making a given circuitefl'ective and which tend to moveinto engagement with each other to form a circuit around said othercircuit, said yieldable contacts being bent back on themselves withtheir free ends engaging said potheads to prevent fatigue of same and toinsure their interengagement when the separating influence is withdrawn.e

4. In a device of the class described, the combination of a support,cooperating confined yieldable contacts therein which are adapted tobeLseparated for making a given circuit eective and which contacts tendto move into engagement with each other to form a circuit around saidother circuit, said yieldable contacts having looped ends to provide aportion for yieldingly engaging said support to prevent fatigue of sameand to insure their interengagement when the separating influence iswithdrawn. Y

5. In a device of the class described, the

combination of a pothead, associated con# tacts carried thereby whichwhen in engagement with each other will complete a circuit through onepath, a. pothead cover carrying spaced contacts for separating saidother contacts and establishing a circuit through another path, and aclamping bracket secured to said pothead for clamping the latter in Kposition and for clamping in position cables entering said pothead.

6. In a device of the character described, the combination with arecessed container, a plurality of cables, means associated with eachcable adapted to have contact with a part of said container and soformed as' t0 ,plete a given circuit, said yieldable contacts springinginto engagement with each other when said other contacts are withdrawnto form a circuit around said other circuit said yieldable contactshaving looped ends to' form a portion for yieldingly engaging saidpothead to insure their engagement when the separating influence iswithdrawn.

8. In a device of the class described, the combination of a potheadprovided with a plurality of recesses, cables disposed in one recess,yieldable contacts disposed in the other recess and having means forelectrical connection with said cables, a removable top for saidpothead, spaced contacts carried thereby which, when electricallyconnected with said yieldable contacts, separate the latter to completea given circuit, said yieldable contacts springing into engagement witheach other when said other contacts are withdrawn to form a circuitaround said other circuit, said yieldable contacts being bent uponthemselves to form a looped end to provide a contact engaging portionand a pothead engaging portion to prevent fatigue of same and to insuretheir engagement when the separating in iuence is Withdrawn.

Signed at Chicago, Illinois, this 13th-day of May, 1925.

' PAUL F. WILLIAMS.

